He said it no less than five times during a six-minute postgame interview at his cubicle.

James had one of the worst playoff games of his career â?? 15 points on 7-for-21 shooting â?? evoking memories of his 3-for-11, eight-point performance against the Dallas Mavericks in Game 4 of the 2011 Finals.

With 3:04 left in the third quarter, James had made just two of 13 field goal attempts, and the Heat were well on their way to their worst playoff loss in franchise history and worst loss of the season.

"I'm putting everything on my chest and on my shoulders," James said. "I've got to be better. It's that simple. My teammates are doing a great job, and I'm not doing my part."

For the third consecutive game, James failed to score at least 20 points. It's the first time he has not reached 20 points in three consecutive games since the 2011 Finals.

James is averaging 16.7 points and shooting 38.9% from the field, including just 23.1% (3-for-13) from three-point range. That's all the more surprising because James set career highs in field goal percentage and three-point shooting percentage this season.

But he has not been at the top of his game against the Spurs. He had an amazing eight-minute stretch in Game 2, but other than that the MVP has been pedestrian.

"I've got to do more. I've got to do more both offensively and defensively," James said. "I've got to put the ball in the basket. I had some great looks. They didn't go."

Six seasons and hundreds of games have passed since the Spurs beat James and the Cleveland Cavaliers in the 2007 Finals, but interestingly, the Spurs are employing a similar game plan against James in 2013: keep him out of the lane and away from the rim and make him shoot long jump shots.

Given that James just turned in the best shooting season of his career, it was a bold move by the Spurs, and it is working so far.

"I'm just missing shots," James said. "They're going under my pick-and-roll. They're daring me to shoot and any time I get into the paint, they're putting two bodies in front of me. When I get in transition, they're putting two bodies in front of me. So I've got to be able to knock down shots. If I knock down shots, it would draw them close to me and give me the lane."

The day before the Spurs-Heat Finals began, James talked about the differences in his game now compared to 2007. He said he is smarter and more mature. He also discussed how the Spurs defended him then.

"They went under a lot of my pick-and-rolls and dared me to shoot," James said nearly a week ago. "Back in '07, I ran a lot of pick-and-rolls. They dared me to shoot it and didn't allow me to get to the paint where I did most of my damage back in '07. If you go under my pick-and-roll now, I'm going to shoot. And I'm confident I'm going to make every last one of them. I'm just more confident in my ability to shoot the ball.

"But at the same time, I also have a lot more weapons this time around going against this team, where in '07 they loaded three guys to me a lot on the strong side of the floor. So like I said, I'm a better player, and you can't dare me to do anything I don't want to do in 2013."

In Game 3, James shot 5-for-7 in the paint and just 2-for-14 outside it. For the series, James is 14-for-24 in the paint and 7-for-30 elsewhere.

James did not attempt a free throw in Game 3 â?? the first time he has not taken a free throw in a game since Dec. 12, 2009, when he was with Cleveland.

"That shows you where my game was tonight," James said.

Heat coach Erik Spoelstra blamed his team's poor defensive effort and said he wasn't as worried about James.

"He'll figure it out. He always figures it out," Spoelstra said. "I'm not concerned about that. We'll work to make sure that he's getting to places he can be comfortable and confident."

James said it's as simple as making shots, and the Spurs tended to agree.

"We haven't stopped anybody," San Antonio coach Gregg Popovich said. "We're trying to play good team defense on everybody."

Danny Green, who played with James in Cleveland, is too smart to write off James.

"Obviously we know what kind of a player LeBron is," Green said. "We know he's not at his best right now. He missed a lot of shots that he normally makes. We're sure Game 4 he's going to come out a lot different.

"We made shots that they didn't. We moved the ball. We didn't turn it over as much. We know they thrive in fast-break transition baskets. So it was hard for them to get into a rhythm.

"But LeBron is not just us stopping him. He's kind of stopped himself out there and we're getting a little lucky."

James wants to watch video to see what else went wrong before making sweeping conclusions. He wasn't happy with Miami's three-point defense and defensive rebounding.

"We have to make adjustments," he said. "As much as we want to get back out there and redeem ourselves, we have to get to the lab (Wednesday) and figure out exactly where the cracks were â?? if it was effort or some of it may have been schemes or whatever the case may be. I think effort was more than anything and we've got to do better."

The Heat have responded well to losses all season and haven't dropped consecutive games since early January. It's well documented that Miami trailed the Indiana Pacers 2-1, the Boston Celtics 3-2 and the Oklahoma City Thunder 1-0 in last season's playoffs. And won all three series.

"It's frustrating when you get smashed like that in a playoff game in the Finals," James said. "When you felt like you came out with a good game plan and nothing works, you're frustrated about it. â?¦ I'm absolutely not happy and very upset.

"But like I said, there's tomorrow. We will prepare. We will be better and I will be better."